Symmetric and Asymmetric Distributions • Emilio Gómez-Déniz Symmetric and Asymmetric Distributions

Total Page:16

File Type:pdf, Size:1020Kb

Symmetric and Asymmetric Distributions • Emilio Gómez-Déniz Symmetric and Asymmetric Distributions Symmetric and Asymmetric Distributions and Symmetric • Emilio Gómez-Déniz • Emilio Symmetric and Asymmetric Distributions Edited by Emilio Gómez-Déniz Printed Edition of the Special Issue Published in Symmetry www.mdpi.com/journal/symmetry Symmetric and Asymmetric Distributions Symmetric and Asymmetric Distributions Theoretical Developments and Applications Editor Emilio Gomez´ -Deni´ z MDPI • Basel • Beijing • Wuhan • Barcelona • Belgrade • Manchester • Tokyo • Cluj • Tianjin Editor Emilio Gomez-D´´ eniz Department of Quantitative Methods and TIDES Institute, University of Las Palmas de Gran Canaria Spain Editorial Office MDPI St. Alban-Anlage 66 4052 Basel, Switzerland This is a reprint of articles from the Special Issue published online in the open access journal Symmetry (ISSN 2073-8994) (available at: https://www.mdpi.com/journal/symmetry/special issues/Symmetric Asymmetric Distributions Theoretical Developments Applications). For citation purposes, cite each article independently as indicated on the article page online and as indicated below: LastName, A.A.; LastName, B.B.; LastName, C.C. Article Title. Journal Name Year, Article Number, Page Range. ISBN 978-3-03936-646-0 (Hbk) ISBN 978-3-03936-647-7 (PDF) c 2020 by the authors. Articles in this book are Open Access and distributed under the Creative Commons Attribution (CC BY) license, which allows users to download, copy and build upon published articles, as long as the author and publisher are properly credited, which ensures maximum dissemination and a wider impact of our publications. The book as a whole is distributed by MDPI under the terms and conditions of the Creative Commons license CC BY-NC-ND. Contents About the Editor .............................................. vii Preface to ”Symmetric and Asymmetric Distributions” ........................................ ix Emilio G´omez-D´eniz, Yuri A. Iriarte, Enrique Calder´ın-Ojeda and H´ector W. G´omez Modified Power-Symmetric Distribution Reprinted from: Symmetry 2019, 11, 1410, doi:10.3390/sym11111410 ................. 1 F´abio V. J. Silveira, Frank Gomes-Silva, C´ıcero C. R. Brito, Moacyr Cunha-Filho, Felipe R. S. Gusm˜ao and S´ılvio F. A. Xavier-Junior ´ Normal-G Class of Probability Distributions: Properties and Applications Reprinted from: Symmetry 2019, 11, 1407, doi:10.3390/sym11111407 ................. 17 H´ector J. G´omez, Diego I. Gallardo and Osvaldo Venegas Generalized Truncation Positive Normal Distribution Reprinted from: Symmetry 2019, 11, 1361, doi:10.3390/sym11111361 ................. 35 Tiago M. Magalh˜aes, Diego I. Gallardo and H´ector W. G´omez Skewness of Maximum Likelihood Estimators in the Weibull Censored Data Reprinted from: Symmetry 2019, 11, 1351, doi:10.3390/sym11111351 ................. 53 Guillermo Mart´ınez-Fl´orez, Inmaculada Barranco-Chamorro, Heleno Bolfarine and H´ector W. Gomez ´ Flexible Birnbaum–Saunders Distribution Reprinted from: Symmetry 2019, 11, 1305, doi:10.3390/sym11101305 ................. 63 Neveka M. Olmos, Osvaldo Venegas, Yolanda M. G´omez and Yuri Iriarte An Asymmetric Distribution with Heavy Tails and Its Expectation–Maximization (EM) Algorithm Implementation Reprinted from: Symmetry 2019, 11, 1150, doi:10.3390/sym11091150 ................. 81 Yolanda M. G´omez, Emilio G´omez-D´eniz, Osvaldo Venegas, Diego I. Gallardo and H´ector W. Gomez ´ An Asymmetric Bimodal Distribution with Application to Quantile Regression Reprinted from: Symmetry 2019, 11, 899, doi:10.3390/sym11070899 ................. 95 Barry C. Arnold, H´ector W. G´omez, H´ector Varela and Ignacio Vidal Univariate and Bivariate Models Related to the GeneralizedEpsilon–Skew–Cauchy Distribution Reprinted from: Symmetry 2019, 11, 794, doi:10.3390/sym11060794 .................107 V. J. Garc´ıa, M. Martel–Escobar and F. J. V´azquez–Polo A Note on Ordering Probability Distributions by Skewness Reprinted from: Symmetry 2018, 10, 286, doi:10.3390/sym10070286 .................121 v About the Editor Emilio Gomez´ -D´eniz (M.S. in Mathematics, M.S. in Economics, and Ph.D. in Economics) is professor of Mathematics at the University of Las Palmas de Gran Canaria (Spain), where he has taught and conducted research for more than 30 years. He is also member of the Institute of Tourism and Sustainable Economic Development (TIDES). His main lines of research focus on distribution theory, Bayesian statistics, robustness, and Bayesian applications in economics, with emphasis in actuarial statistics, tourism, education, sports, electronic engineering, health economics, etc. He has published more than 150 articles, most of them with JCR impact factor according to Web of Science and his work has been cited more than 1000 times on Google Scholar with an h-index of 16 and an i10 index of 35. He is currently the editor or member of the editorial board of the Spanish Journal of Statistics (SJS), Chilean Journal of Statistics, Mathematical Problems in Engineering, Risks, Risk Magazine, and Journal of Financial and Risk Management (Reviewer Board) and Statistical Methodology and Mathematical Reviews in the past. He has also acted and regularly acts as reviewer for more than 100 international journals. His academic leadership is further reflected through collaborative research with more than 50 leading international scientists worldwide. He is the author of many books on mathematics education and research, including ”Actuarial Statistics. Theory and Applications”, Prentice Hall (in Spanish). He has organized and participated in many international conferences and seminars. In addition, he has visited, as guest researcher and speaker, the University of Melbourne, the University of Kuwait, the University of Cantabria, the University of Antofagasta (Chile), the University of Barcelona, and the University of Granada, among others. In 2008, he was awarded the prestigious IV Julio Castelo Matran´ International Insurance Award, sponsored by the Mapfre Foundation and also recognized by his university for excellence in teaching. vii Preface to ”Symmetric and Asymmetric Distributions” This Special Issue contains nine chapters selected after a comprehensive peer review process. Each chapter exclusively adheres to the topic specified in this Special Issue. The Associate Editor wants to especially thank all the authors who made this Special Issue possible, and all the anonymous reviewers for their altruistic effort and help in reviewing and for their excellent suggestions and critical reviews of the submitted manuscripts. All the chapters are written in the format of a research article for scholarly journals, i.e., title, abstract, and development, with an extensive bibliography at the end of the paper. All of them include real applications that will undoubtedly be useful for other researchers and graduate students who conduct similar research. I express my gratitude to MPDI for publishing this book, to Ms. Celina Si, Section Managing Editor, for her work and patience, and last but not least to my family for their support and cooperation. Emilio Gomez´ -D´eniz Editor ix S symmetry S Article Modified Power-Symmetric Distribution Emilio Gómez-Déniz 1, Yuri A. Iriarte 2, Enrique Calderín-Ojeda 3 and Héctor W. Gómez 2,* 1 Department of Quantitative Methods in Economics and TIDES Institute, University of Las Palmas de Gran Canaria, 35017 Las Palmas de Gran Canaria, Spain; [email protected] 2 Departamento de Matemáticas, Facultad de Ciencias Básicas, Universidad de Antofagasta, Antofagasta 1240000, Chile; [email protected] 3 Centre for Actuarial Studies, Department of Economics, The University of Melbourne, Melbourne, VIC 3010, Australia; [email protected] * Correspondence: [email protected] Received: 2 October 2019; Accepted: 13 November 2019; Published: 15 November 2019 Abstract: In this paper, a general class of modified power-symmetric distributions is introduced. By choosing as symmetric model the normal distribution, the modified power-normal distribution is obtained. For the latter model, some of its more relevant statistical properties are examined. Parameters estimation is carried out by using the method of moments and maximum likelihood estimation. A simulation analysis is accomplished to study the performance of the maximum likelihood estimators. Finally, we compare the efficiency of the modified power-normal distribution with other existing distributions in the literature by using a real dataset. Keywords: maximum likelihood; kurtosis; power-normal distribution 1. Introduction Over the last few years, the search for flexible probabilistic families capable of modeling different levels of bias and kurtosis has been an issue of great interest in the field of distributions theory. This was mainly motivated by the seminal work of Azzalini [1]. In that paper, the probability density function (pdf) of a skew-symmetric distribution was introduced. The expression of this density is given by g(z; λ)=2 f (z)G(λz), z, λ ∈ R, (1) where f (·) is a symmetric pdf about zero; G(·) is an absolutely continuous distribution function, which is also symmetric about zero; and λ is a parameter of asymmetry. For the case where f (·) is the standard normal density (from now on, we reserve the symbol φ for this function), and G(·) is the standard normal cumulative distribution function (henceforth, denoted by Φ), the so-called skew-normal (SN) distribution with density φ ( λ)= φ( )Φ(λ ) λ ∈ R Z z; 2 z z , z, , (2) is obtained. We use the notation Z ∼SN(λ) to denote the random variable Z with pdf given by Equation (2). A generalization
Recommended publications
  • A Skew Extension of the T-Distribution, with Applications
    J. R. Statist. Soc. B (2003) 65, Part 1, pp. 159–174 A skew extension of the t-distribution, with applications M. C. Jones The Open University, Milton Keynes, UK and M. J. Faddy University of Birmingham, UK [Received March 2000. Final revision July 2002] Summary. A tractable skew t-distribution on the real line is proposed.This includes as a special case the symmetric t-distribution, and otherwise provides skew extensions thereof.The distribu- tion is potentially useful both for modelling data and in robustness studies. Properties of the new distribution are presented. Likelihood inference for the parameters of this skew t-distribution is developed. Application is made to two data modelling examples. Keywords: Beta distribution; Likelihood inference; Robustness; Skewness; Student’s t-distribution 1. Introduction Student’s t-distribution occurs frequently in statistics. Its usual derivation and use is as the sam- pling distribution of certain test statistics under normality, but increasingly the t-distribution is being used in both frequentist and Bayesian statistics as a heavy-tailed alternative to the nor- mal distribution when robustness to possible outliers is a concern. See Lange et al. (1989) and Gelman et al. (1995) and references therein. It will often be useful to consider a further alternative to the normal or t-distribution which is both heavy tailed and skew. To this end, we propose a family of distributions which includes the symmetric t-distributions as special cases, and also includes extensions of the t-distribution, still taking values on the whole real line, with non-zero skewness. Let a>0 and b>0be parameters.
    [Show full text]
  • Simulation of Moment, Cumulant, Kurtosis and the Characteristics Function of Dagum Distribution
    264 IJCSNS International Journal of Computer Science and Network Security, VOL.17 No.8, August 2017 Simulation of Moment, Cumulant, Kurtosis and the Characteristics Function of Dagum Distribution Dian Kurniasari1*,Yucky Anggun Anggrainy1, Warsono1 , Warsito2 and Mustofa Usman1 1Department of Mathematics, Faculty of Mathematics and Sciences, Universitas Lampung, Indonesia 2Department of Physics, Faculty of Mathematics and Sciences, Universitas Lampung, Indonesia Abstract distribution is a special case of Generalized Beta II The Dagum distribution is a special case of Generalized Beta II distribution. Dagum (1977, 1980) distribution has been distribution with the parameter q=1, has 3 parameters, namely a used in studies of income and wage distribution as well as and p as shape parameters and b as a scale parameter. In this wealth distribution. In this context its features have been study some properties of the distribution: moment, cumulant, extensively analyzed by many authors, for excellent Kurtosis and the characteristics function of the Dagum distribution will be discussed. The moment and cumulant will be survey on the genesis and on empirical applications see [4]. discussed through Moment Generating Function. The His proposals enable the development of statistical characteristics function will be discussed through the expectation of the definition of characteristics function. Simulation studies distribution used to empirical income and wealth data that will be presented. Some behaviors of the distribution due to the could accommodate both heavy tails in empirical income variation values of the parameters are discussed. and wealth distributions, and also permit interior mode [5]. Key words: A random variable X is said to have a Dagum distribution Dagum distribution, moment, cumulant, kurtosis, characteristics function.
    [Show full text]
  • A New Parameter Estimator for the Generalized Pareto Distribution Under the Peaks Over Threshold Framework
    mathematics Article A New Parameter Estimator for the Generalized Pareto Distribution under the Peaks over Threshold Framework Xu Zhao 1,*, Zhongxian Zhang 1, Weihu Cheng 1 and Pengyue Zhang 2 1 College of Applied Sciences, Beijing University of Technology, Beijing 100124, China; [email protected] (Z.Z.); [email protected] (W.C.) 2 Department of Biomedical Informatics, College of Medicine, The Ohio State University, Columbus, OH 43210, USA; [email protected] * Correspondence: [email protected] Received: 1 April 2019; Accepted: 30 April 2019 ; Published: 7 May 2019 Abstract: Techniques used to analyze exceedances over a high threshold are in great demand for research in economics, environmental science, and other fields. The generalized Pareto distribution (GPD) has been widely used to fit observations exceeding the tail threshold in the peaks over threshold (POT) framework. Parameter estimation and threshold selection are two critical issues for threshold-based GPD inference. In this work, we propose a new GPD-based estimation approach by combining the method of moments and likelihood moment techniques based on the least squares concept, in which the shape and scale parameters of the GPD can be simultaneously estimated. To analyze extreme data, the proposed approach estimates the parameters by minimizing the sum of squared deviations between the theoretical GPD function and its expectation. Additionally, we introduce a recently developed stopping rule to choose the suitable threshold above which the GPD asymptotically fits the exceedances. Simulation studies show that the proposed approach performs better or similar to existing approaches, in terms of bias and the mean square error, in estimating the shape parameter.
    [Show full text]
  • Exponentiated Kumaraswamy-Dagum Distribution with Applications to Income and Lifetime Data Shujiao Huang and Broderick O Oluyede*
    Huang and Oluyede Journal of Statistical Distributions and Applications 2014, 1:8 http://www.jsdajournal.com/content/1/1/8 RESEARCH Open Access Exponentiated Kumaraswamy-Dagum distribution with applications to income and lifetime data Shujiao Huang and Broderick O Oluyede* *Correspondence: [email protected] Abstract Department of Mathematical A new family of distributions called exponentiated Kumaraswamy-Dagum (EKD) Sciences, Georgia Southern University, Statesboro, GA 30458, distribution is proposed and studied. This family includes several well known USA sub-models, such as Dagum (D), Burr III (BIII), Fisk or Log-logistic (F or LLog), and new sub-models, namely, Kumaraswamy-Dagum (KD), Kumaraswamy-Burr III (KBIII), Kumaraswamy-Fisk or Kumaraswamy-Log-logistic (KF or KLLog), exponentiated Kumaraswamy-Burr III (EKBIII), and exponentiated Kumaraswamy-Fisk or exponentiated Kumaraswamy-Log-logistic (EKF or EKLLog) distributions. Statistical properties including series representation of the probability density function, hazard and reverse hazard functions, moments, mean and median deviations, reliability, Bonferroni and Lorenz curves, as well as entropy measures for this class of distributions and the sub-models are presented. Maximum likelihood estimates of the model parameters are obtained. Simulation studies are conducted. Examples and applications as well as comparisons of the EKD and its sub-distributions with other distributions are given. Mathematics Subject Classification (2000): 62E10; 62F30 Keywords: Dagum distribution; Exponentiated Kumaraswamy-Dagum distribution; Maximum likelihood estimation 1 Introduction Camilo Dagum proposed the distribution which is referred to as Dagum distribution in 1977. This proposal enable the development of statistical distributions used to fit empir- ical income and wealth data, that could accommodate heavy tails in income and wealth distributions.
    [Show full text]
  • Suitability of Different Probability Distributions for Performing Schedule Risk Simulations in Project Management
    2016 Proceedings of PICMET '16: Technology Management for Social Innovation Suitability of Different Probability Distributions for Performing Schedule Risk Simulations in Project Management J. Krige Visser Department of Engineering and Technology Management, University of Pretoria, Pretoria, South Africa Abstract--Project managers are often confronted with the The Project Evaluation and Review Technique (PERT), in question on what is the probability of finishing a project within conjunction with the Critical Path Method (CPM), were budget or finishing a project on time. One method or tool that is developed in the 1950’s to address the uncertainty in project useful in answering these questions at various stages of a project duration for complex projects [11], [13]. The expected value is to develop a Monte Carlo simulation for the cost or duration or mean value for each activity of the project network was of the project and to update and repeat the simulations with actual data as the project progresses. The PERT method became calculated by applying the beta distribution and three popular in the 1950’s to express the uncertainty in the duration estimates for the duration of the activity. The total project of activities. Many other distributions are available for use in duration was determined by adding all the duration values of cost or schedule simulations. the activities on the critical path. The Monte Carlo simulation This paper discusses the results of a project to investigate the (MCS) provides a distribution for the total project duration output of schedule simulations when different distributions, e.g. and is therefore more useful as a method or tool for decision triangular, normal, lognormal or betaPert, are used to express making.
    [Show full text]
  • Reliability Test Plan Based on Dagum Distribution
    International Journal of Advanced Statistics and Probability, 4 (1) (2016) 75-78 International Journal of Advanced Statistics and Probability Website: www.sciencepubco.com/index.php/IJASP doi: 10.14419/ijasp.v4i1.6165 Research paper Reliability test plan based on Dagum distribution Bander Al-Zahrani Department of Statistics, King Abdulaziz University, Jeddah, Saudi Arabia E-mail: [email protected] Abstract Apart from other probability models, Dagum distribution is also an effective probability distribution that can be considered for studying the lifetime of a product/material. Reliability test plans deal with sampling procedures in which items are put to test to decide from the life of the items to accept or reject a submitted lot. In the present study, a reliability test plan is proposed to determine the termination time of the experiment for a given sample size, producers risk and termination number when the quantity of interest follows Dagum distribution. In addition to that, a comparison between the proposed and the existing reliability test plans is carried out with respect to time of the experiment. In the end, an example illustrates the results of the proposed plan. Keywords: Acceptance sampling plan; Consumer and Producer’s risks; Dagum distribution; Truncated life test 1. Introduction (1) is given by t −d −b Dagum [1] introduced Dagum distribution as an alternative to the F (t;b;s;d) = 1 + ; t > 0; b;s;d > 0: (2) Pareto and log-normal models for modeling personal income data. s This distribution has been extensively used in various fields such as income and wealth data, meteorological data, and reliability and Further probabilistic properties of this distribution are given, for survival analysis.
    [Show full text]
  • On the Computation of Multivariate Scenario Sets for the Skew-T and Generalized Hyperbolic Families Arxiv:1402.0686V1 [Math.ST]
    On the Computation of Multivariate Scenario Sets for the Skew-t and Generalized Hyperbolic Families Emanuele Giorgi1;2, Alexander J. McNeil3;4 February 5, 2014 Abstract We examine the problem of computing multivariate scenarios sets for skewed distributions. Our interest is motivated by the potential use of such sets in the stress testing of insurance companies and banks whose solvency is dependent on changes in a set of financial risk factors. We define multivariate scenario sets based on the notion of half-space depth (HD) and also introduce the notion of expectile depth (ED) where half-spaces are defined by expectiles rather than quantiles. We then use the HD and ED functions to define convex scenario sets that generalize the concepts of quantile and expectile to higher dimensions. In the case of elliptical distributions these sets coincide with the regions encompassed by the contours of the density function. In the context of multivariate skewed distributions, the equivalence of depth contours and density contours does not hold in general. We consider two parametric families that account for skewness and heavy tails: the generalized hyperbolic and the skew- t distributions. By making use of a canonical form representation, where skewness is completely absorbed by one component, we show that the HD contours of these distributions are near-elliptical and, in the case of the skew-Cauchy distribution, we prove that the HD contours are exactly elliptical. We propose a measure of multivariate skewness as a deviation from angular symmetry and show that it can explain the quality of the elliptical approximation for the HD contours.
    [Show full text]
  • A Study of Non-Central Skew T Distributions and Their Applications in Data Analysis and Change Point Detection
    A STUDY OF NON-CENTRAL SKEW T DISTRIBUTIONS AND THEIR APPLICATIONS IN DATA ANALYSIS AND CHANGE POINT DETECTION Abeer M. Hasan A Dissertation Submitted to the Graduate College of Bowling Green State University in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY August 2013 Committee: Arjun K. Gupta, Co-advisor Wei Ning, Advisor Mark Earley, Graduate Faculty Representative Junfeng Shang. Copyright c August 2013 Abeer M. Hasan All rights reserved iii ABSTRACT Arjun K. Gupta, Co-advisor Wei Ning, Advisor Over the past three decades there has been a growing interest in searching for distribution families that are suitable to analyze skewed data with excess kurtosis. The search started by numerous papers on the skew normal distribution. Multivariate t distributions started to catch attention shortly after the development of the multivariate skew normal distribution. Many researchers proposed alternative methods to generalize the univariate t distribution to the multivariate case. Recently, skew t distribution started to become popular in research. Skew t distributions provide more flexibility and better ability to accommodate long-tailed data than skew normal distributions. In this dissertation, a new non-central skew t distribution is studied and its theoretical properties are explored. Applications of the proposed non-central skew t distribution in data analysis and model comparisons are studied. An extension of our distribution to the multivariate case is presented and properties of the multivariate non-central skew t distri- bution are discussed. We also discuss the distribution of quadratic forms of the non-central skew t distribution. In the last chapter, the change point problem of the non-central skew t distribution is discussed under different settings.
    [Show full text]
  • A Formulation for Continuous Mixtures of Multivariate Normal Distributions
    A formulation for continuous mixtures of multivariate normal distributions Reinaldo B. Arellano-Valle Adelchi Azzalini Departamento de Estadística Dipartimento di Scienze Statistiche Pontificia Universidad Católica de Chile Università di Padova Chile Italia 31st March 2020 Abstract Several formulations have long existed in the literature in the form of continuous mixtures of normal variables where a mixing variable operates on the mean or on the variance or on both the mean and the variance of a multivariate normal variable, by changing the nature of these basic constituents from constants to random quantities. More recently, other mixture-type constructions have been introduced, where the core random component, on which the mixing operation oper- ates, is not necessarily normal. The main aim of the present work is to show that many existing constructions can be encompassed by a formulation where normal variables are mixed using two univariate random variables. For this formulation, we derive various general properties. Within the proposed framework, it is also simpler to formulate new proposals of parametric families and we provide a few such instances. At the same time, the exposition provides a review of the theme of normal mixtures. Key-words: location-scale mixtures, mixtures of normal distribution. arXiv:2003.13076v1 [math.PR] 29 Mar 2020 1 1 Continuous mixtures of normal distributions In the last few decades, a number of formulations have been put forward, in the context of distribution theory, where a multivariate normal variable represents the basic constituent but with the superpos- ition of another random component, either in the sense that the normal mean value or the variance matrix or both these components are subject to the effect of another random variable of continuous type.
    [Show full text]
  • Final Paper (PDF)
    Analytic Method for Probabilistic Cost and Schedule Risk Analysis Final Report 5 April2013 PREPARED FOR: NATIONAL AERONAUTICS AND SPACE ADMINISTRATION (NASA) OFFICE OF PROGRAM ANALYSIS AND EVALUATION (PA&E) COST ANALYSIS DIVISION (CAD) Felecia L. London Contracting Officer NASA GODDARD SPACE FLIGHT CENTER, PROCUREMENT OPERATIONS DIVISION OFFICE FOR HEADQUARTERS PROCUREMENT, 210.H Phone: 301-286-6693 Fax:301-286-1746 e-mail: [email protected] Contract Number: NNHl OPR24Z Order Number: NNH12PV48D PREPARED BY: RAYMOND P. COVERT, COVARUS, LLC UNDER SUBCONTRACT TO GALORATHINCORPORATED ~ SEER. br G A L 0 R A T H [This Page Intentionally Left Blank] ii TABLE OF CONTENTS 1 Executive Summacy.................................................................................................. 11 2 In.troduction .............................................................................................................. 12 2.1 Probabilistic Nature of Estimates .................................................................................... 12 2.2 Uncertainty and Risk ....................................................................................................... 12 2.2.1 Probability Density and Probability Mass ................................................................ 12 2.2.2 Cumulative Probability ............................................................................................. 13 2.2.3 Definition ofRisk ..................................................................................................... 14 2.3
    [Show full text]
  • A Family of Skew-Normal Distributions for Modeling Proportions and Rates with Zeros/Ones Excess
    S S symmetry Article A Family of Skew-Normal Distributions for Modeling Proportions and Rates with Zeros/Ones Excess Guillermo Martínez-Flórez 1, Víctor Leiva 2,* , Emilio Gómez-Déniz 3 and Carolina Marchant 4 1 Departamento de Matemáticas y Estadística, Facultad de Ciencias Básicas, Universidad de Córdoba, Montería 14014, Colombia; [email protected] 2 Escuela de Ingeniería Industrial, Pontificia Universidad Católica de Valparaíso, 2362807 Valparaíso, Chile 3 Facultad de Economía, Empresa y Turismo, Universidad de Las Palmas de Gran Canaria and TIDES Institute, 35001 Canarias, Spain; [email protected] 4 Facultad de Ciencias Básicas, Universidad Católica del Maule, 3466706 Talca, Chile; [email protected] * Correspondence: [email protected] or [email protected] Received: 30 June 2020; Accepted: 19 August 2020; Published: 1 September 2020 Abstract: In this paper, we consider skew-normal distributions for constructing new a distribution which allows us to model proportions and rates with zero/one inflation as an alternative to the inflated beta distributions. The new distribution is a mixture between a Bernoulli distribution for explaining the zero/one excess and a censored skew-normal distribution for the continuous variable. The maximum likelihood method is used for parameter estimation. Observed and expected Fisher information matrices are derived to conduct likelihood-based inference in this new type skew-normal distribution. Given the flexibility of the new distributions, we are able to show, in real data scenarios, the good performance of our proposal. Keywords: beta distribution; centered skew-normal distribution; maximum-likelihood methods; Monte Carlo simulations; proportions; R software; rates; zero/one inflated data 1.
    [Show full text]
  • A Guide on Probability Distributions
    powered project A guide on probability distributions R-forge distributions Core Team University Year 2008-2009 LATEXpowered Mac OS' TeXShop edited Contents Introduction 4 I Discrete distributions 6 1 Classic discrete distribution 7 2 Not so-common discrete distribution 27 II Continuous distributions 34 3 Finite support distribution 35 4 The Gaussian family 47 5 Exponential distribution and its extensions 56 6 Chi-squared's ditribution and related extensions 75 7 Student and related distributions 84 8 Pareto family 88 9 Logistic ditribution and related extensions 108 10 Extrem Value Theory distributions 111 3 4 CONTENTS III Multivariate and generalized distributions 116 11 Generalization of common distributions 117 12 Multivariate distributions 132 13 Misc 134 Conclusion 135 Bibliography 135 A Mathematical tools 138 Introduction This guide is intended to provide a quite exhaustive (at least as I can) view on probability distri- butions. It is constructed in chapters of distribution family with a section for each distribution. Each section focuses on the tryptic: definition - estimation - application. Ultimate bibles for probability distributions are Wimmer & Altmann (1999) which lists 750 univariate discrete distributions and Johnson et al. (1994) which details continuous distributions. In the appendix, we recall the basics of probability distributions as well as \common" mathe- matical functions, cf. section A.2. And for all distribution, we use the following notations • X a random variable following a given distribution, • x a realization of this random variable, • f the density function (if it exists), • F the (cumulative) distribution function, • P (X = k) the mass probability function in k, • M the moment generating function (if it exists), • G the probability generating function (if it exists), • φ the characteristic function (if it exists), Finally all graphics are done the open source statistical software R and its numerous packages available on the Comprehensive R Archive Network (CRAN∗).
    [Show full text]